DOC: Fix EX01 in DataFrame.duplicated (#33416)

Author: farhanreynaldo

pandas/core/frame.py

@@ -4740,6 +4740,73 @@ def duplicated(
         Returns
         -------
         Series
+            Boolean series for each duplicated rows.
+
+        See Also
+        --------
+        Index.duplicated : Equivalent method on index.
+        Series.duplicated : Equivalent method on Series.
+        Series.drop_duplicates : Remove duplicate values from Series.
+        DataFrame.drop_duplicates : Remove duplicate values from DataFrame.
+
+        Examples
+        --------
+        Consider dataset containing ramen rating.
+
+        >>> df = pd.DataFrame({
+        ...     'brand': ['Yum Yum', 'Yum Yum', 'Indomie', 'Indomie', 'Indomie'],
+        ...     'style': ['cup', 'cup', 'cup', 'pack', 'pack'],
+        ...     'rating': [4, 4, 3.5, 15, 5]
+        ... })
+        >>> df
+            brand style  rating
+        0  Yum Yum   cup     4.0
+        1  Yum Yum   cup     4.0
+        2  Indomie   cup     3.5
+        3  Indomie  pack    15.0
+        4  Indomie  pack     5.0
+
+        By default, for each set of duplicated values, the first occurrence
+        is set on False and all others on True.
+
+        >>> df.duplicated()
+        0    False
+        1     True
+        2    False
+        3    False
+        4    False
+        dtype: bool
+
+        By using 'last', the last occurrence of each set of duplicated values
+        is set on False and all others on True.
+
+        >>> df.duplicated(keep='last')
+        0     True
+        1    False
+        2    False
+        3    False
+        4    False
+        dtype: bool
+
+        By setting ``keep`` on False, all duplicates are True.
+
+        >>> df.duplicated(keep=False)
+        0     True
+        1     True
+        2    False
+        3    False
+        4    False
+        dtype: bool
+
+        To find duplicates on specific column(s), use ``subset``.
+
+        >>> df.duplicated(subset=['brand'])
+        0    False
+        1     True
+        2    False
+        3     True
+        4     True
+        dtype: bool
         """
         from pandas.core.sorting import get_group_index
         from pandas._libs.hashtable import duplicated_int64, _SIZE_HINT_LIMIT